Javascript: how to validate dates in format MM-DD-YYYY?

Question

I saw a potential answer here but that was for YYYY-MM-DD: JavaScript date validation

I modified the code code above for MM-DD-YYYY like so but I still can't get it to work:

String.prototype.isValidDate = function()  {      var IsoDateRe = new RegExp("^([0-9]{2})-([0-9]{2})-([0-9]{4})$");      var matches = IsoDateRe.exec(this);      if (!matches) return false;      var composedDate = new Date(matches[3], (matches[1] - 1), matches[2]);      return ((composedDate.getMonth() == (matches[1] - 1)) &&       (composedDate.getDate() == matches[2]) &&       (composedDate.getFullYear() == matches[3])); } 

How can I get the above code to work for MM-DD-YYYY and better yet MM/DD/YYYY?

Thanks.

Answer 1

function isValidDate(date) {     var matches = /^(\d{1,2})[-\/](\d{1,2})[-\/](\d{4})$/.exec(date);     if (matches == null) return false;     var d = matches[2];     var m = matches[1] - 1;     var y = matches[3];     var composedDate = new Date(y, m, d);     return composedDate.getDate() == d &&             composedDate.getMonth() == m &&             composedDate.getFullYear() == y; } console.log(isValidDate('10-12-1961')); console.log(isValidDate('12/11/1961')); console.log(isValidDate('02-11-1961')); console.log(isValidDate('12/01/1961')); console.log(isValidDate('13-11-1961')); console.log(isValidDate('11-31-1961')); console.log(isValidDate('11-31-1061')); 

It works. (Tested with Firebug, hence the console.log().)

Answer 2

function isValidDate(date) {         var valid = true;          date = date.replace('/-/g', '');          var month = parseInt(date.substring(0, 2),10);         var day   = parseInt(date.substring(2, 4),10);         var year  = parseInt(date.substring(4, 8),10);          if(isNaN(month) || isNaN(day) || isNaN(year)) return false;          if((month < 1) || (month > 12)) valid = false;         else if((day < 1) || (day > 31)) valid = false;         else if(((month == 4) || (month == 6) || (month == 9) || (month == 11)) && (day > 30)) valid = false;         else if((month == 2) && (((year % 400) == 0) || ((year % 4) == 0)) && ((year % 100) != 0) && (day > 29)) valid = false;         else if((month == 2) && ((year % 100) == 0) && (day > 29)) valid = false;         else if((month == 2) && (day > 28)) valid = false;      return valid; } 

This checks for valid days in each month and for valid leap year days.